ZhenAn Small Tungsten Crucible Manufacturer
The main raw materials used in tungsten crucible
Tungsten crucible is mainly made of tungsten powder raw material.
Tungsten plate rolling can be divided into hot rolling, warm rolling and cold rolling.
Due to the high deformation resistance of tungsten, ordinary rollers cannot fully meet the requirements for rolling tungsten plates, and rollers of special materials should be used.
During rolling, the rolls must be preheated, and the preheating temperature is 100 to 350°C according to different rolling conditions. The blank can be processed only when the relative density (ratio of actual density and theoretical density) is greater than 90%.
The processing performance is good when the blank density is between 92 and 94%. The billet opening temperature of hot rolling is between 1350 and 1500°C. If the deformation process parameters of billet opening are not selected properly, the billet will be delamination.
The starting temperature of warm rolling is 1200°C, and the thickness of a hot-rolled plate with a thickness of 8 mm can reach 0.5 mm after warm rolling.
Due to the high deformation resistance of the tungsten plate, the roll body bends and deforms during rolling, resulting in uneven thickness of the plate along the width direction. When changing rolls or rolling mills, the plate may crack due to uneven deformation in various parts.
The plastic-brittle transition temperature of the 0.5 mm thick plate is still at or above room temperature, and the sheet is brittle. The sheet should be rolled to 0.2 mm at 200~500°C. In the later stage of rolling, the tungsten sheets are thin and long. In order to ensure that the plate is heated evenly, it is often coated with graphite or molybdenum disulfide, which is not only beneficial to the heating of the plate, but also has a lubrication effect during processing.